[Clinical research on multi-drug resistant and extensive drug-resistant tuberculosis in Japan]

To know the number of patients with MDR-TB and XDR-TB newly diagnosed annually and the number of those with continuously culture-positive in spite of continued treatment.

To fill the questionnaire sent to all the TB hospitals in Japan and to investigate the number of beds for TB, MDR-TB cases newly admitted to each hospital in 2006 and chronic bacillary cases in spite of continued treatment.

We sent the questionnaires to all the TB hospitals in Japan and 81% of 270 hospitals replied. As the result, 93 MDR-TB were newly hospitalized (12 cases were with XDR-TB). 76 cases of them were newly diagnosed MDR-TB. Almost after 1 year treatment, patients with XDR-TB showed lower negative conversion rate than other MDR-TB (42.9% vs 63.8%) and higher fatality rate (42.9% vs 7.2%). Excluding above 93 new MDR-TB cases, 103 cases with chronic MDR-TB including 44 cases with XDR-TB had been treated during the observation period, 84 case had been hospitalized and other 19 cases at OPD.

Since 2000, extensive multi-resistant (XDR) TB has been a global topic. In Japan, nation-wide survey on 2002 showed the ratio of MDR and XDR were 1.9% and 0.6% respectively out of 3122 TB stains investigated. XDR/MDR rate was higher than those in other countries. Our clinical based investigation showed total XDR/MDR rate was 28.6% (56/196) and it was similar to that of previous bacteriological survey in 2002.

We investigated the number of patients with MDR-TB and XDR-TB newly diagnosed in 2006 and the number of those who were continuously culture-positive. The survey showed that there were 196 patients with MDR-TB, and 56 patients of them (28.6%) were with XDR-TB. Many of them were in the districts of Kinki area and Kanto-Shinetsu area and 70% of them had been treated in the hospitals belonging to the National Hospital Organization.